Generally speaking, before installing any new program on a machine, particularly on Windows, it is recommanded to take a few precautions :

save the image of the hard disk through a software dedicated to this task. Norton Ghost is well known for this purpose.

when needed, complete the saving of the image of the disk by saving the modified files

use an up-to-date and active anti-virus

Furthermore, it is highly advised to have installed a firewall before any connecting to Internet.

The greatest care has been brought to the realization of the programs that are proposed on this site. However I cannot reasonnably, as even the greatest software publishers, assume any responsability concerning the consequences of the execution or installation of these programs. The user is strongly encouraged to proceed as above described.